How can I be assured that the lids and bowls are locked into place?

Babycook® Classic:

When attaching the cooking bowl lid and water reservoir lid, be sure to lock the lids in by turning them counter clockwise until you hear a slight “click.”When placing the bowl on the Babycook unit, be sure to turn the bowl clockwise in order to properly lock it into place until you hear a “click.”

Babycook® Pro/ Pro 2X:

Babycook Pro models have several safety mechanisms to make sure the appliance does not steam or blend unless it is fully closed. To lock the bowl into place, hold the bowl using the handle and position on the base. Then turn clockwise until you hear a click and the bowl will not turn any further. This is one safety mechanism. The appliance will not work until the top lid is also locked into place. Lock the lid by pressing on the heat-resistant rubber arrow on top of the locking arm that holds the lid. You will hear a slight click. Once the bowl and locking arm are locked into place, you will be able to steam and blend using Babycook Pro.